pragma once and for all

Fix all the whitespace

- remove trailing whitespace
- remove duplicate blank lines
- remove blank lines at end of files

Fix licenses

SELFOUR-701 Condition variable implementation

SELFOUR-701 VKA managed versions of sem, bin_sem, mutex & recursive_mutex

libsel4sync: replaced aep with notification

The only non-local changes in this commit are renaming of fields of
sync_bin_sem_t and sync_recursive_mutex_t from aep to notification.
Nothing outside of this library should operate on those fields directly.